1. Field of the Invention
This invention relates to pulleys and in particular to multiple groove pulleys for multiple-element endless power transmission belts made primarily of polymeric material.
2. Prior Art Statement
Power transmission belts made primarily of polymeric material and wherein each has a plurality of integral longitudinally extending belt elements are well known and widely used in industry. However, the present practice is to require special pulleys for each particular type of belt whereby the cost of the resulting power transmission system is increased.
One type of multiple element polymeric belt which has been standardized by the belt industry is a so-called V-ribbed belt which has the usual tension section and load-carrying section and wherein the compression section thereof has a plurality of longitudinally extending ribs each of V-shaped cross-sectional configuration. V-ribbed belts of this type are described in Engineering Standard Publication IP-26 for V-ribbed belts (H, J, K, L, and M cross sections) c. 1977 by The Rubber Manufacturers Association, Inc., 1901 Pennsylvania Avenue; Washington, D. C. 20006. One common feature of the belts having H through M cross sections is that each V-shaped rib thereof has an included angle of 40.degree. between its outside surfaces yet each of these belts has a different center spacing between immediately adjacent ribs.
In using V-ribbed belts it will be appreciated that the number of belt elements provided on a belt will vary whereby the previous practice has been to provide special pulleys for each belt used as a function of the number of belt elements. In addition, each belt cross section L through M requires special pulleys even when the number of belt elements is the same from one type of belt cross section to another. Accordingly, it would be desirable to provide a pulley construction for V-ribbed belts which would have at least parts thereof useable with more than one particular V-ribbed belt.
A pulley construction has been proposed heretofore which utilizes a number of so-called stock sections to define a pulley having a plurality of grooves and such pulley construction is disclosed in U.S. Pat. No. 2,632,333. The teaching of this patent appears to be provision of a pulley which permits a wide variation in groove size to fit individual belts.